CVE-2026-62757: Windows Schannel Security Feature Bypass Vulnerability
Improper verification of cryptographic signature in Windows Schannel allows an unauthorized attacker to bypass a security feature over a network.
CSIRTS triage
- What
- Improper cryptographic signature verification in Schannel allows security feature bypass over the network.
- Who is affected
- Systems relying on Schannel for TLS/SSL authentication across networks.
- Urgency
- Medium priority; signature verification bypass affects authentication integrity but not currently exploited.
- Action
- Apply Windows security updates addressing CVE-2026-62757 when available.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62757
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2026-627570.26% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 17% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2026-62757 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
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